Various dispensing valves or control valves have been used in the past in connection with fluid dispensing systems for controlling fluid flow. "Bag-in box" fluid dispensing systems in particular employ a bag containing fluid, a valve for dispensing fluid from the bag, and a box, with the bag being placed in an interior of the box for handling and storage purposes. To dispense fluid from the bag, the valve is exposed, typically by opening a portion of the box. The valve controls fluid flow from the bag. In some bag-in-box constructions, the bag is not filled through the valve, only emptied. Instead, the bag may be filled through a opening which is sealed off during installation and attachment of the valve to the bag.
Some concerns in the dispensing valve or control valve industry in general include reducing the costs of manufacturing the valve. A related concern is the ease of assembly and manufacture. In the past, some valves have employed intricate and complex parts. Other valves have numerous small parts. Some valves are unreliable in that the valves may leak or may be moved from the open to the closed position inadvertently. In addition, some valves are awkward to operate by hand.
With respect to the bag-in-box industry, there are several significant concerns relating to the dispensing valve. A major concern is minimizing the cost to manufacture the valves. Many bag-in-box systems are disposable, meaning that the bag with the dispensing valve is a disposable item. Another concern is reducing the profile of the valve. In some bag filling and valve attachment machines, the size of the dispensing valve is limited. Also, space limitations in the box may exist for the valve.
Other considerations in the bag-in-box industry, and possibly other fluid dispensing systems, relate to the operation of the valve. One concern is whether the valve requires the application of an external force or forces to maintain the valve in the open position. This concern relates to whether the valve is hands free in the open position. In some valves, the valve automatically moves to the closed position from the open position when the operator's hand or hands are removed. Another concern is the ease in which the valve may be moved from the open to the closed position, and from the closed position to the open position. In general, bag-in-box dispensing systems do not provide much support of the dispensing valve in relation to the bag. In some cases, the bag is fairly flexible and no external rigid support of the valve is provided. Some valves must be manipulated with two hands to move the valve between positions.
Other concerns include whether the valve contains a safety lock feature to prevent accidental opening of the valve from the closed position, such as may occur during handling or transport. A further concern with bag-in-box systems is the versatility of the valve to be used in either a manual system, wherein the user opens the valve to fill a container and then closes the valve for future use, and the systems approach, wherein the valve is connected to a fluid dispensing system with the fluid being pumped from the bag to a dispensing station having on/off controls. An additional concern, especially with inexpensive valves, is the reliability of remaining leak free in the closed position during operation. Some valves employ separate o-ring seals, which are prone to problems such as inconsistent performance overtime.
It is clear that there has existed a long and unfilled need in the prior art for a dispensing valve that addresses the above noted concerns in a cost effective and reliable manner.